Ceylon (true) cinnamon may be safer than the more common cassia (Chinese) cinnamon due to the compound, coumarin, present in cassia cinnamon which data suggests may be toxic to the liver in quantities of one or more teaspoons per day. However, you don’t have to be concerned about getting too manyoxalates as you do with turmeric. While cinnamon is chock full of antioxidants, it may not be an effective treatment fordiabetes.